Domenico Scarlatti began his compositional career following in the footsteps of his father Alessandro Scarlatti by writing operas, chamber cantatas, and other vocal music, but he is most remembered for his 555 keyboard sonatas, written between approximately 1719 and 1757. It is believed that Domenico received most of his musical training from family members, but his father was the dominant figure in his life. It was Alessandro who arranged Domenico's first appointment, as organist and composer for Naples' Cappella Reale, and wanted him to continue with vocal music despite the enormous talent he had shown for keyboard music. Domenico was sent to Venice in 1705, where he met Handel, and in 1708 to Rome to become maestro di cappella to the exiled queen of Poland, Maria Casimira, and later, head of the Cappella Giulia. In these positions, he composed his operas and serenatas, and some sacred vocal works. It was also in Rome where he developed a friendship with the Portuguese ambassador, the Marquis de Fontes, which eventually led to Scarlatti's being appointed master of the royal chapel by João V of Portugal in 1719. Scarlatti was also teacher to the royal family, particularly princess Maria Barbara. Scarlatti had already written approximately 50 keyboard pieces before coming to Lisbon, but wrote many more for his students, which also included Carlos de Seixas. When Maria Barbara married Spanish prince Ferdinando, Scarlatti followed her to Spain. His first publication, 30 sonatas called "Essercizi," was issued in 1738 and sold throughout Europe. Although as King and Queen, Ferdinando and Maria Barbara introduced opera into Spain's cultural life, Scarlatti did not write any for them. However, he did assist in their private musical soirées, again writing cantatas and working with singers such as the castrato Farinelli. Scarlatti also continued to teach, and, in the last six years of his life, concentrated on organizing his sonatas in manuscripts. These one-movement sonatas are recognized as cornerstones of the keyboard repertoire, a bridge between the Baroque and the galant styles of keyboard writing. They demonstrate his facility in adapting rhythms found in contemporary Iberian popular music and his inventiveness in creating themes and developing interesting harmonies, and like Bach's music, have been performed on many instruments other than harpsichord, piano, or organ.